Means sprung. Used in 'I Like Big Butts' by SirMixAlot. 'rung' at the end is shouted... spa-RUNG!

I like big butts and I can not lie
You other brothers can't deny
That when a girl walks in with an itty bitty waist
And a round thing in your face
You get spa-RUNG!!
Wanna pull up tough
Cuz you notice that butt was stuffed
...
and so on